a government report concludes it's not a bad idea. >> it could mean the beginning. the end for gu guantanamo bay. diane feinstein asked for a study four years ago and got the report this month. >> reporter: 166 detainees could be housed safely in american prisons, according to a federal report released today. senator feinstein concludes that president obama's controversial plan to move detainees to the u.s. could work. she says 373 people charged or convicted of terrorism are already held in u.s. facilities without security problems. and the reporticize the defense diameter -- the report says the defense department has room for more. >> guantanamo is a real stain on our country's image abroad. >> reporter: he's been to guantanamo and interviewed dozens of inmates. moving the detainees could make a difference. >> there'll be a lot more human rights groups and liberties groups pushing to have a trial or release, and i think it'll be stronger in america. and that could make the difference in finally these men will get a trial. >> i think americans would be on edge. >>